MYOFASCIAL PAIN SYNDROME
Repetitive micro-traumata (injuries), unresolved single injury, inflammation, poor posture or maladaptive movement habits at play or at work, stress, lack of sleep, or any combination of the above will produce tightness or abnormal contraction of skeletal muscles. The investing fascia becomes taut and bound down. Circulation to and from the muscles is decreased, resulting in the accumulation of the end-products of muscle metabolism, particularly lactic acid and potassium ions. Localized areas of muscle tenderness called TRIGGER POINTS are formed. These are extremely sensitive and will fire impulses (under the slightest provocation such as pressure and stretching), to distant tissues, producing pain and consequent loss of motion at remote locations. This causes the further accumulation of muscle toxins, more muscle and fascial tightness, more pain, etc., perpetuating the MYOFASCIAL PAIN cycle.
This is an extremely common cause of pain anywhere in the body: head, face, neck, shoulders, chest, arms, low back, buttocks, legs, feet, etc. To understand more about this ubiquitous problem, a few definitions and explanations are in order:
Fascia is a tough connective tissue lining, covering and investing muscles, and, indeed, all cells, tissues and organs. Fascia is three-dimensional and is continuous throughout the body. Anything affecting fascia in one area is manifested to some extent in all body regions.
Pain is an abnormal, unpleasant EMOTIONAL and sensory experience caused by actual or perceived injury. This results in the stimulation of nerve endings called nociceptors. These impulses are transmitted to the spinal cord and then to the brain where they register as pain.
Trigger points (TrP) are foci of hyperirritability in muscle, fascia or ligaments (connecting bone to bone as in joints). They are characterized by taut fibrous bands, a twitch response when stimulated, and constant areas of referred pain. The pain patterns thus produced are called myofascial pain syndromes. There are several types and locations of trigger points:
Active TrPs are always tender. They prevent full lengthening of the muscle and weaken it. Direct compression, stretching, or other sources of irritation such as accumulation of the toxic chemical products of muscle metabolism or lack of oxygen will ignite the TrP. From it, localized pain is produced in a specific area with associated autonomic changes. These may include increased or reduced skin temperature, sweating or dryness. The area of referred pain is often distant from the TrP.
Latent TrPs may not be painful to pressure, but result in muscle weakness and restricted motion. There are also secondary and satellite TrPs, the explanation of which is beyond the scope of this article.
Ligamentous TrPs are found in lax, stretched ligaments as a result of aging, trauma and/or poor posture, particularly those ligaments involved in the support of the axial (vertebral column and pelvis) or appendicular skeleton.
Periosteal TrPs are found on the surface of bone usually at the site of ligament or tendon attachment and related to tension on that area from stretched ligaments.
Alignment Or Postural Factors: Gravity in combination with aging, long term poor posture, and/or repeated injury causes laxity of the axial (trunk and pelvis) and appendicular skeletal ligaments. This is most relevant in the spine and pelvis. Tightness of the psoas major muscle combined with weakness of the abdominal muscles, particularly the pelvic attachment of the obliques and recti, combine to perpetuate a downward tilting of the pelvis and an increase in the lumbar lordosis. Thus, the ligaments connecting the pelvis to the vertebral column and to the lower extremities are stretched and their nociceptors depolarized, initiating the pain cycle. The same applies to the pelvic and low back muscles which now are tightened and ischemic.
Other Perpetuating Factors: include leg length disparity or pelvic tilt; hyperpronation (inward rolling of the foot); nutritional, metabolic, endocrine, postural and emotional factors as well as bacterial or viral infections or parasitic infestations.
Major Myofascial Pain Syndromes: The trigger points I have found most frequently related to pain complaints in our practice are located in the following muscles: iliopsoas, quadratus lumborum, gluteus medius, gluteus minimus, piriformis, hamstrings, trapezius, levator scapula, scalenus anticus.
Here are a few pointers to help you in your own pain management:
Passive stretching can be dangerous: "no pain no gain" is a rule with strict limitations. The inadequately trained person stretching you has no conception of your pain or tolerance. Stretch yourself or let a trained therapist help.
The presence of a TrP in a muscle can be suspected when stretching or attempting to strengthen a muscle group is either fruitless or results in aggravation of pain with the pattern being repetitive. Don’t attempt to stretch or strengthen a muscle with TrPs.
Any discomfort while stretching should be experienced in the belly of the muscle, NOT at the point of attachment to bone or in the tendon.
Remember: not everybody needs to stretch and not every muscle needs to be stretched. Older people with extremely lax ligaments may depend on hypertonic muscles to support unstable skeletal structures and may react poorly to attempts to stretch.
Treatment of myofascial pain syndromes consists principally of the following measures and is part of the program available at Catskill Rehabilitation & Sports Medicine:
Identify and correct all possible perpetuating factors. Of particular importance are: correction of postural imbalances with short leg lifts; correction of faulty foot mechanics with orthotics.
Identify and treat all trigger points with ultra sound and low volt electrical stimulation, dry needling, injection with a local anaesthetic, acupuncture, spray and stretch with a topical local anaesthetic or any combination of the above.
- Trigger point injections, massage, soft tissue mobilization.
Re-establish normal, restorative sleep using muscle relaxants, acupuncture or a combination of these.
Pain relief with medication ranging from acetominophen through non-steroid anti-inflammatories and aspirin to short term narcotics, if necessary.
Careful, appropriate stretching and strengthening are essential components of any successful treatment and rehabilitation program. Your physical therapist and I will be your guides in such a program.
Aerobic exercise, instituted carefully and progressed gradually to tolerance is vital to recovery and prevention of recurrence.